Removal of tissue

ABSTRACT

To reduce damage to surrounding tissue while fragmenting some tissue such as for example not damaging the capsular wall while removing the lens during cataract removal surgery or not damaging artery or vein walls during bypass surgery while freeing the artery or vein to be transplanted, an incision is made for the insertion of surface--a handpiece tip. The tip is rotated and reciprocated ultrasonically at the same time so that tissue is fragmented by the combined motion of a fragmenting surface perpendicular to the surface and at an angle to the surface many times during a single revolution or part of a revolution.

RELATED CASE

This application is a continuation-in-part of U.S. Pat. No. 5,911,699,issued Jun. 15, 1999, patent application Ser. No. 08/828,928 filed Mar.28, 1997, which is a continuation-in-part of U.S. Pat. No. 5,722,945,issued Mar. 3, 1998, patent application Ser. No. 08/625,909 filed Apr.1, 1996, which is a continuation-in-part of U.S. patent application Ser.No. 08/372,866 filed Jan. 13, 1995, abandoned, which is a continuationof U.S. patent application Ser. No. 08/035,985 filed Mar. 22, 1993,abandoned, which is a continuation-in-part of U.S. patent applicationSer. No. 07/759,937 filed Sep. 16, 1991, abandoned, which is acontinuation-in-part of U.S. patent application Ser. No. 07/680,292filed Apr. 4, 1991, abandoned, which is a continuation-in-part of U.S.patent application Ser. No. 07/553,975, filed in the name of Aziz Y.Anis on Jul. 17, 1990, now U.S. Pat. No. 5,222,959, issued Jun. 29,1993, entitled for REMOVAL OF TISSUE.

BACKGROUND OF THE INVENTION

This invention relates to the removal of tissue from the body such asfor example removal of cataracts from the eye.

It is known to remove diseased tissue from the body by fragmenting,crushing or otherwise making the tissue flowable while in the body andthen aspirating it. In one known class of surgical techniques of thistype specifically intended for the removal of cataracts: (1) an incisionis made along the superior corneal margin from about 10 to 2 o'clock (12o'clock is the location closest to the top of the head of the patient)approximately 10 mm in chord length; (2) an incision is made in thecapsular wall; and (3) the cataract is removed. The anterior chamber ismaintained substantially formed during the operation by means of acontinuous inflow of irrigating solution.

In one prior art technique of this class for removing a cataract, thenucleus is expressed out of the eye and the cortex is removed by aprocess of irrigation and aspiration. In another prior art technique ofthis class for removing the cataract, the nucleus is removed with avectis and about 0.1 milliliter of viscoelastic compound or irrigatingfluid is introduced into the capsular bag to separate the capsularwalls. With the capsular walls separated, a wedge of the cortex isengaged in the aspiration port of a cannula and peeled toward the centerand then aspirated to remove it. This process is repeated so that thelayers of the cortex are peeled and then aspirated inwardly through thecannula, layer by layer, until the intact capsular bag (except for thehorizontal incision) is completely empty and clean.

This technique of removing the cataract is disclosed by Anis, Aziz Y.,"Illustrated Step-by-Step Description of the Anis Dry Extra CapsularCataract Extraction Technique With In-the-Bag Lens Implementation";Seminars in Oiothalmology, v. 1, N. 2 (June), 1986, pp. 113-129 and thetechnique is compared with other such techniques of this class.

Two prior art types of instruments which aid in the fragmentation andaspiration of the lens nucleus to permit extraction through a smallincision are machines disclosed in U.S. Pat. No. 3,589,363 to AntonBanko et al.; U.S. Pat. No. 3,902,495 to Steven N. Weiss; U.S. Pat. No.3,693,613 to Charles Kelman et al.; and U.S. Pat. No. 4,041,947 toSteven N. Weiss et al. These machines are intended in the prior art tofragment a lens nucleus using ultrasonic vibrations to aid theirrigation/aspiration of the lens. The ultrasonic vibrations laterallyreciprocate the tip of an instrument to fracture the cataract afterwhich it can be aspirated.

A further type of machine is disclosed in U.S. Pat. No. 4,908,015 issuedto Anis on Mar. 13, 1990. This patent describes a machine that rotates asolid member having blades extending from it to grind the lens.

These tissue removal techniques have several disadvantages, such as: (1)the machines used in the techniques risk tearing the capsular wall withthe reciprocating ultrasonic vibration tools or with the rotatingblades; (2) under some circumstances, they require large incisions in orremoval of parts of the capsular wall; and (3) they may require the useof several different instruments and/or machines.

Still another type of prior art technique for removing cataracts uses amachine disclosed in U.S. Pat. No. 3,996,935 to Banko issued Dec. 14,1976. This type of machine has cooperating jaw-like members, one ofwhich rotates inside the other to break up the lens by shearing sectionsof it. It aspirates fragments through the instrument. This type ofinstrument has a disadvantage in that it can break the capsular wall andis relatively complex. Part of the disadvantage comes from the teachingthat it may be rotated manually or mechanically without a correspondingteaching of the rate of rotation required for efficient use.

Still another prior art instrument includes a small rotary magneticcutter that is injected through the capsular wall and a means forapplying magnetic fields that control the magnetic cutter in position.The small magnetic cutter is rotated as it moves from position toposition in the capsular bag and to abrade or cut the lens that is to beremoved.

This instrument has several disadvantages, such as: (1) it is relativelycomplicated and expensive because of the need to remotely control thesmall cutter; and (2) does not incorporate any mechanism for aspiratingthe lens particles as they are abraded from the lens.

In still another prior art device disclosed in U.S. Pat. No. 4,002,169,small retractable wires are rotated in a range of 5 rpm to 16,000 rpm.There is no teaching of selecting the speed for surface discriminationand the device relies on blunt surfaces to avoid damage to the capsularwall instead. This device has the disadvantages of: (1) providing arelatively slow cutting velocity range with blades not shaped forcavitation or turbulance; (2) not providing a range of velocitiessufficient to form small particles that can be aspirated through a smallhole; and (3) not providing for aspiration during fragmenting, thusblocking visibility with particles.

Each of these prior art types of instruments includes a handpiece and aconsole. The handpiece is held by the surgeon and includes an operativetip that, at one point in time, enters the capsular sac to fragment andremove the cataract. The console includes controls for the handpiecesuch as those that control the direction of movement and speed ofmovement of the tip, rate of flow of liquids, the suction or aspirationpressure and the drivers that apply power to the handpiece at theappropriate values. Generally, the consoles are designed together with aparticular type of handpiece used in a specialized technique of ocularsurgery.

A still further type of instrument is disclosed in U.S. Pat. No.4,504,264 to Kelman issued Mar. 12, 1985. This patent discloses aninstrument that reciprocates a cutting tip ultrasonically and oscillatesit rotationally about its longitudinal axis at a rate of one hertzthrough an angle of between five degrees to 60 degrees.

A similar United States patent, U.S. Pat. No. 5,176,677 to Wuchinichdescribes oscillation through a larger arc and states that therotational motion is not limited as to direction or speed. It describesa device in which rotation of a beveled tip cuts tissue with reversalaccommodating asymmetrical morphology to cut tissue that is more easilyseparated from one side than the other. This patent teaches thatrotation from 61 to 360 degrees is sufficient for most purposes butrotation through any arc is possible through appropriate control butdoes not teach any mechanism or range that is preferable other than themotor being capable of operating from zero to 200 r.p.m. but as much as3,000 r.p.m. with an appropriate bearing.

Because of dwell time at each change of rotational direction, therepeated changes of direction and speed limitations inherent in thedirection changes, these two instruments do not provide the advantage ofpositive breaking of the tissue into particles small enough to not causeplugging of the tip nor impede visibility.

The prior art arrangement has several disadvantages, such as forexample: (1) it is difficult for the surgeon to use the most moderntechniques without investing substantial amounts of money in purchasingadditional consoles for the newer instruments; (2) for each newhandpiece designed for a particular technique, the surgeon must adapt todifferent controls in the console itsself rather than relying uponcontrols with which he is already familiar; (3) the handpieces aresubject to plugging, poor visibility into the eye and excessive pressureon the capsular wall from movement of large particles; (4) differentequipment is necessary to remove vitreous liquids; (5) the aspiratingforce pulls large masses of tissue when the tip is normal to the tissue,thus occluding the opening; (6) deep coring is not possible to break thetissue into particles; and (7) vitreous liquids and semisolids are notabsorbed but pull back when aspirating pressure is released.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the invention to provide a noveltechnique for tissue removal.

It is a further object of the invention to provide a novel instrumentfor fragmenting and removing a cataract during cataract removal surgerywith low risk of damage to the capsular wall.

It is a still further object of the invention to provide a novelinstrument designed to fragment tissue without damage to the nearbytissue such as for example not damaging the capsular wall while removingthe lens during cataract removal surgery or not damaging artery or veinwalls while removing cancerous tissue near the vein or artery.

It is a still further object of the invention to provide a novelinstrument and method for removing tissue that reduces the size of thetissue and aspirates them while maintaining good visibility.

It is a still further object of the invention to provide a novelsurgical instrument that reduces the size of particles of tissuesufficiently to avoid occlusion of an aspirating device.

It is a still further object of the invention to provide a novelinterface that permits the connection of a phacotmesis handpiece toconsoles designed specifically for other ocular surgery such as consolesdesigned originally to cooperate with a phacoemulsification handpiece.

It is a still further object of the invention to provide an instrumentcapable of vitrectomy and removal of cateracts with the same handpiece.

It is a still further object of the invention to provide an instrumentfor removing the tissue that relies upon multiple mechanisms forfragmenting tissue including cavitation of hydrated tissue and torsionaltwisting of fiberous material to failure of the fibers.

It is a still further object of the invention to provide an instrumentfor removing tissue that does not depend on vacuum pressure to breaksmaller parts of tissue away from larger parts.

In accordance with the above and further objects of the invention, anincision is made for the insertion of a surface-discriminating,fragmenting tool. The surface-discriminating, fragmenting tool fragmentsand permits aspiration of high mass, rough-surface, rigid tissue withoutdamaging nearby smooth, flexible, low mass walls. The tool fragmentssome tissue but avoids fragmenting other tissue by discriminatingbetween tissues. This discrimination is based on one or more of severalfactors including: (1) the rigidity of the tissue; (2) the amount ofmass of the tissue; (3) the angle of the tissue to the direction ofmovement of the tool; (4) the roughness of the surface of the tissue;and (5) the size and shape of the surface of the tissue to the extentthe size and shape affect the tendency of the negative pressure createdby aspiration and/or irrigation to move the tissue toward thesurface-discriminating, fragmenting tool.

The surface discrimination of the tool is controlled by moving surfaceswhich fragment diseased tissue on impact, referred to as phacotmesis,and cause cavitation forces that further fragment and mix fragments oftissue, and provide a twisting section that breaks fibers to avoidpulling unbroken large particles into the tip to occlude it. Thesurfaces move at a rate of speed slow enough so that the moreintegrated, more flexible, lower mass and smoother tissue is moved awaywithout fragmenting. The tissue is not constrained by opposed shearforces of the tool as in some prior art rotating tools nor is the highermass, rigid tissue moved significantly as a bulk.

The surfaces of the instrument fragment tissue that: (1) is stiffer andhas a higher modulus of rigidity; and (2) is at an angle to the cuttingedge closer to 90 degrees and receives less force moving it away. Thus,the surgeon removing a cataract adjusts the speed of movement of thetool surfaces, the aspirating and irrigation forces, the rake angle ofthe tip and the cavitation level as controlled by the position of thetool surface, the velocity and the shape of the moving surface. Theadjustment is made to fragment the cortex because of its higher mass,modulus of elasticity and projections in the path of the tool surfacesbut to move the capsular wall because of its lower mass, lower modulusand fewer projections closer to 90 degrees and not fragment it.

In one embodiment, a moving, fragmenting surface moves at an angle withthe normal to a cataract surface, which angle is obtuse and generallyclose to being perpendicular to the normal in such a manner as to mixparticles and to cause or aid ultrasonic motion normal to the tissue incausing cavitation and torsional twisting forces that fragment and mixthe cataract particles while maintaining the direct force on thecataract that could accelerate tissue against the capsular wallrelatively low. In a preferred embodiment, the fragmenting surface ismoved ultrasonically along the normal while it is moving at an angle tothe normal such as by rotating continuously at least through several 360degree rotations in one direction. Its effective range for cavitationand twisting is in the range of 1,400 r.p.m. and 10,000 r.p.m. andoptimally 4,000 r.p.m.

The aspiration pressure is more effective within the moving surfaces ofthe rotating tip. It is low enough to pull the fragmented tissue andtissue to be fragmented but it does not hold the smooth flexiblecapsular wall against movement away from the moving surfaces of thetool. The rotating surfaces move the smooth wall outwardly and providesome counter pressure to the aspirating pressure inside the fragmentingzone. The vibrating speed and rotational speed can be adjusted to powderthe cateract so as to maintain good visibility and ease of aspirationand can be adjusted for vitrectomy.

In the case of cataract removal surgery, a small incision of two toseven millimeters and preferably three millimeters is made in the scleraalong the corneal border at 12 o'clock and another incision of similardimension or a round hole is made in the anterior capsular wall. Theinstrument is inserted and fragments the lens matter without fragmentingthe capsular wall. The factors useful in surface-discriminatory,fragmenting differ from eye to eye or tissue to tissue and may beselected in accordance with the surgeon's observations.

These factors are the speed of the moving surfaces with respect to thetissue, the holding pressure from aspirating vacuum and irrigatingliquid, the location and position of the moving surfaces, the rake angleof the cutting edge of the moving surfaces and the shape of the portionsof the moving surfaces most related to cavitation. These factors areestablished by the surgeon as a function of the mass of the capsularwall and the mass of the tissue to be fragmented, the stiffness andsmoothness of the capsular wall or other healthy smooth tissue and thehardness and flexibility of the tissue.

In one embodiment, moving surfaces of the fragmenting tool hit the cellsat a substantially tangential angle and distort them or cut them withtheir leading edges while the trailing edges create cavitation thatfurther breaks and mixes the tissue without imparting such force to thetissue in a direction that may injure the capsular wall. For large andrigid or for rough surfaces, the shear force and cavitation issufficient for fragmentation whereas for more flexible, lower mass andsmoother surfaces, the leading edges and the cavitation tend to move thesurface away and thus avoid fragmentation. The aspirating port or portstend to pull the fragmented material into the interior of the tool.

In a preferred embodiment, a tubular member has a central, aspiratingchannel along its longitudinal axis with one end having a fragmentingtip and the other end being adapted to rotate the tube. In oneembodiment, the cavitation is at low frequency below the ultrasonicfrequency range. In a preferred embodiment, the tip is rotatedcontinuously in one direction for more than one 360 degree cycle and atthe same time ultrasonically reciprocated.

In the preferred embodiment, a blunt tip with a central opening isrotated and reciprocated with aspirating pressure being applied to thecentral opening to remove particles. The ultrasonic reciprocating ornear ultrasonic reciprocating combined with rotation causes cavitationand powders some of the cataract, particularly the hydrated cataracttissue. However, it also impacts tissue with the annular edge around thecentral opening, catches tissue so that the rotation twists the fiberousmaterial. The speed of rotation is maintained at a value that twists thefibers to torsional failure so that those portions of the fiberousmaterial not fragmented by cavitation are nonetheless maintainedsufficiently small as to not occlude the central opening. Indeed, unlikeprior art instruments, the preferred embodiment may be used normal tothe cataract and inserted to considerable depth without occludingalthough with only ultrasonic vibration, the tip would be occluded andfail to aspirate particles efficiently. Thus, it would be necessary touse lollipopping with two instruments whereas with the preferredembodiment the extra cutting tool is not needed.

Vitreous material is broken up and aspirated easily unlike the prior artinstruments which only pulled the vitreous material without separatingit from the mass so that it pulled back and could not be aspirated oronly aspirated with difficultly. The instrument of this invention twiststhe vitreous free from the mass and aspirates the vitreous materialfaster than a refractory cannula which only slowly severs pieces inshearing between two surfaces and aspirates them.

As can be understood from the above description, the technique andinstrument of this invention have several advantages, such as: (1) theyselectively fragment some tissue without damaging other nearby tissue;(2) they are able to fragment, mix and aspirate tissue, and in the caseof cataract removal, while maintaining good visibility; and (3) the samehandpiece can perform vitrectomy.

SUMMARY OF THE DRAWINGS

The above noted and other features of the invention will be betterunderstood from the following detailed description when considered withreference to the accompanying drawings, in which:

FIG. 1 is a simplified, elevational view of a handpiece and controlconsole for fragmenting and removing cataracts in accordance with anembodiment of the invention;

FIG. 2 is an enlarged, perspective view of a portion of the embodimentof FIG. 1;

FIG. 3 is a fragmentary, sectional view of another portion of theembodiment of FIG. 1;

FIG. 4 is a fragmentary, perspective view of another embodiment of bladeportion usable as a replacement for the blade portion in the embodimentof FIG. 1;

FIG. 5 is a plan view of the embodiment of FIG. 4;

FIG. 6 is a fragmentary, elevational view, partly sectioned and partlydiagramatic of another embodiment of handpiece;

FIG. 7 is a fragmentary, elevational view of another embodiment of toolportion;

FIG. 8 is a top view of the embodiment of FIG. 7;

FIG. 9 is an elevational, right hand view of the embodiment of FIG. 7;

FIG. 10 is a fragmentary, elevational view of a tool tip whichrepresents a variation of the tool tip of FIGS. 7-9;

FIG. 11 is a diagramatic, top view of a tool tip illustrating a firststep useful in making the embodiment of FIGS. 7-9;

FIG. 12 is a fragmentary, elevational view of the tool tip shown in FIG.11;

FIG. 13 is an elevational view of a tool tip illustrating a second stepin preparing the embodiment of FIGS. 7-9;

FIG. 14 is a top view of the tool tip shown in FIG. 13;

FIG. 15 is a fragmentary, perspective view illustrating an additionalstep in preparing the embodiment of FIGS. 7-9;

FIG. 16 is a perspective view illustrating still another possible stepin preparing a tool tip similar to the embodiments of FIGS. 7-9;

FIG. 17 is a block diagram of a process for using the instrument ofFIGS. 1-6 to remove a cataract;

FIG. 18 is a simplified, cross-sectional view of an eye and cataractremoval handpiece tip illustrating a portion of the technique of thisinvention;

FIG. 19 is a fragmentary, elevational view, partly sectioned and partlydiagramatic of still another embodiment of handpiece;

FIG. 20 is a sectional view of another embodiment of handpiece;

FIG. 21 is a sectional view of a tip usable in the embodiment of FIG.20;

FIG. 22 is a block diagram of a console interface for connecting any ofseveral different consoles to a phacotmesis handpiece and a phacotmesishandpiece;

FIG. 23 is a schematic circuit diagram of an interface circuit; and

FIG. 24 is a block diagram of an ultrasonic driver circuit.

DETAILED DESCRIPTION

In FIG. 1, there is shown an elevational view of asurface-discriminating, fragmenting handpiece 10, connecting tubing 23and a console 21. The handpiece 10 includes a drive portion 11, a bladeportion 14 and a tubular sleeve portion 12. The tubular sleeve portion12 includes a tubular casing 13 and an inner tubular aspirating driveshaft or sleeve 18. The drive portion 11 houses the motor, an on-offswitch 20 and connectors for irrigating fluid and aspirating vacuumpressure.

The blade portion 14 includes blades 17A and 17B each of which isfastened to the rotatable tubular shaft 18 at diametrically oppositelocations on the shaft 18 and each of which has a corresponding one ofblunt tips 15A and 15B turned inwardly to avoid cutting. The outertubular casing 13 includes within it a movable sleeve 19A so that uponlongitudinal movement of a button 19 with respect to the outer casing 13of the tubular sleeve portion 12, the blades 17A and 17B move apart in afragmenting position in response to one direction of movement of thebutton 19 and are forced within the movable sleeve 19A within thetubular sleeve portion 12 against the pressure of the spring-like blades17A and 17B upon movement in the other direction of the button 19 to fitwithin a smaller incision such as a 2 millimeter opening. The blades 17Aand 17B are narrower in the direction of rotation and blunt on thetrailing edge to cause cavitation.

With this arrangement, the blades 17A and 17B may be moved together forinsertion of the handpiece 10 into a capsular sac through a relativelysmall aperture and then permitted to expand outwardly so that uponrotation of the blade portion 14, the cortex and nucleus are fragmentedwithin the capsular sac. In the embodiment of FIG. 1, the handpiece 10includes a motor for rotating the shaft and a connecting tubing 23 foraspirating fragments. The console 21 may include for cooperation withthe handpiece 10, a standard source of electrical power, a vacuumsource, a source of irrigating liquid and a pump for irrigating liquid.These elements are conventional and are not part of the invention exceptinsofar as they cooperate with the handpiece 10.

In FIG. 2, there is shown an enlarged, fragmentary perspective view ofthe blade portion 14 of the tool assembly having first and second blades17A and 17B with corresponding blunt ends 15A and 15B. The blades 17Aand 17B are sufficiently flexible in the embodiment of FIG. 2 to expanduntil they form outwardly, curved, cutting surfaces extending beyond thesurfaces of the outer casing or shaft 13 (FIG. 1) and have sharpenededges 32 and 34 tangentially to or pointing inwardly from the circles ofrotation formed as they rotate. When the blades 17A and 17B are pulledinwardly by movement of the sleeve 19A upwardly, they fit within acylinder having a diameter of less than two millimeters.

While the embodiment of FIGS. 1 and 2 have blades with sharpened edgespointing tangentially to or inwardly from the direction of rotation,sharpened edges are not necessary and the angle of attack or rake angleof the sharpened edges may vary. However, the angle of attack may betangential to the path of rotation or any larger or smaller angle. Forthis purpose, any one of several multiple blade portions 14 with theirattached inner drive shaft 18 may be inserted into the sleeve portion 12and drive portion 11. The blade portion is selected by the physician andone fact in such selection is the angle of attack of the blades.

To permit compressing of the blades 17A and 17B into a protectivesleeve, the tubular sleeve portion 12 includes the three coaxial sleeves18, 19A and 13 (FIG. 1) in that order outwardly from the central axis.The blades 17A and 17B are mounted to the inner tubular drive sleeve 18for rotation therewith and there is a space between the sleeves 18 andl9A for irrigating fluid to flow. The movable sleeve 19A is affixed tothe button 19 (FIG. 1) and is movable axially with respect to innerdrive sleeve 13 to engage the blades 17A and 17B and to compress theminwardly.

In FIG. 3, there is shown a fragmentary longitudinal sectional view ofthe tubular sleeve portion 12 and the drive portion 11: (1) havingwithin the sleeve portion 12, the inner rotatable tubular aspiratingdrive shaft or sleeve 18, the movable tubular protective sleeve 19A andthe outer sleeve 13; and (2) having within the drive portion 11, a motor40 for rotating the inner aspirating drive shaft 18 to turn the blades17A and 17B (FIG. 1), a hollow aspirating tube 27 to apply vacuumpressure to the interior of the inner shaft 18, an irrigating tube 17communicating with the movable sleeve 19A to apply irrigating fluidthrough the sleeve 19A and through electrical wires 25 to control themotor 40. The inner shaft 18 is coupled at one end 42 to the outputshaft 44 of the motor 40 for rotation therewith and to a tubularconnection 45 for aspiration.

As shown in this view, the outer sleeve 13 supports within it themovable sleeve 19A with the button 19 extending through a slot in theouter sleeve 13 by which the movable sleeve 19A may be moved upwardlyand downwardly to bend the blades 17A and 17B inwardly for retraction orto permit them to expand outwardly in the cutting position to theirnormal position for rotating and in some embodiments still further undercentifugal force when rotating. However, the moment of inertia of theblades 17A and 17B is sufficient so that the centrifugal force does notforce the points to point outwardly and only the bent flat surface ispresented to the outer sleeve 13 during rotation. It is spaced from themovable tube 19A to permit irrigating fluid to flow therebetween andcontains in its center, an opening 15 which extends downwardly foraspiration of tissues.

To provide irrigating fluids, the irrigating tube 17 is connectedthrough a cable 23 to the console 21 (FIG. 1) from which irrigatingliquid is pumped through the tube 17 around the motor 40 and to thespace between the movable tube 19A and the inner shaft 18 to supplyirrigating fluid to the capsular sac. To aspirate tissue, the centralopening 15 in the inner shaft 18 passes through an opening 29 in thewall of the inner shaft 18 and communicates through a sealed circularring 31 with the aspirating conduit 25. The connection 45 passes aroundthe motor 40 and through the cable 23 to the console 21 (FIG. 1) whichapplies slight negative pressure to aspirate tissue. The cable 23 alsocarries electrical conductors for the motor 40 which are connected inseries between the switch 20, and a source of electrical power in theconsole 21 and the motor 40.

To use the embodiment of FIGS. 1-3, an incision is made for theinsertion of the surface-discriminating, fragmenting handpiece 10. Thesurface-discriminating, fragmenting handpiece 10 fragments and permitsaspiration of the tissue but avoids damaging nearby smooth, flexiblewalls. Instead, it fragments rougher, more rigid surfaces of highermasses. This surface discrimination is controlled by the moving surfaceof the blades 17A and 17B, which permit the diseased tissue to bestrained or cut by the blades 17A and 17B and further fragmented by theforces of cavitation within their fragmenting zone but which move at arate of speed and have openings between them of such a size that themore integrated, lower mass or more flexible and smoother tissue doesnot fall within their fragmenting zone but is moved away from the movingsurfaces. The aspirating pressure, cavitation and turbulence iscounteracted or attenuated within the sphere of the rotating ring toavoid damage to the flat surface tissue.

In the case of cataract removal surgery, a small incision of two toseven millimeters and preferably three millimeters is made in theschlera along the corneal border at 12 o'clock and another incision ofsimilar dimensions is made in the capsular wall. The instrument isinserted and fragments the higher mass, more rigid, rougher lens withoutfragmenting the capsular wall.

The actual time that the fragmenting zone must be open to fragmentdiseased tissue without injuring smooth walls differs from eye to eye ortissue to tissue and may be selected in accordance with the surgeon'sobservations prior to use. It is a function of: (1) the rigidity of thetissue; (2) the mass of the tissue; (3) the angle of the tissue to thedirection of movement of the tool; (4) the roughness of the surface; and(5) the effect of the negative pressure pulling the tissue inwardly suchas the aspiration vacuum pressure which may vary in its effect dependingon the size and shape of the tissue.

The surface discrimination of the tool is controlled by moving surfaceswhich cause the diseased tissue to fragment under impact, referred to asphacotmesis, and cavitation forces, referred to as phacocoelosis, butwhich move at a rate of speed slow enough so that the more integrated,more flexible, lower mass and smoother tissue is moved away withoutfragmenting. The surfaces of the instrument fragment tissue that: (1) isstiff; (2) has a high mass and large inertia; and (3) is at an angle tothe cutting edge close to 90 degrees.

To take advantage of the differences between the tissue to be fragmentedand the lower, more flexible tissue, the surgeon removing a cataractadjusts the speed of movement of the tool surfaces, the aspirating andirrigation rates, the rake angle of the leading edge of the bladesurfaces and the cavitation level as controlled by the position of theblade surfaces, the velocity and the shape of the moving surfaces,especially the trailing edge of the blades. The adjustments are made tofragment the cortex because of its higher mass, modulus of elasticityand projections in the path of the tool surfaces and to move thecapsular wall away from the blades because of its lower mass, lowermodulus and fewer projections closer to 90 degrees. Tips are replaced tochange the rake angle and cavitation surfaces.

The aspiration pressure is more effective within the moving surfaces ofthe rotating tip. It is low enough to pull the fragmented tissue andtissue to be fragmented but does not hold the smooth wall againstmovement nor pull it inwardly. The rotating surfaces move the smoothwall outwardly and provide some counter pressure to the aspiratingpressure inside the fragmenting zone. In one embodiment, radially,inwardly, extending edges further pull and mix tissue within thefragmenting zone.

To better describe this and other embodiments, some special terminologyis useful. For purposes of this description, the words, "low power" meanless than one horsepower (1.341 kilowatts). In this description, thewords, "motion resistance" mean the resistance of a portion of tissue tomovement when impacted by a moving tool surface caused by the inertia ofthe tissue and the effect of the inertia of other tissue connected to ittaking into consideration the flexibility of the connecting tissue.

In this description, the words, "fragmenting velocity" mean the minimumvelocity of a moving surface of a tool with respect to predeterminedstationary tissue that the moving surface of the tool impacts that issufficient to cause strain in the tissue of at least ten percent of thedistance moved by the entire tissue mass and to break the tissue bycombined strain, cutting and cavitation effects. This value is specificfor a predetermined stationary tissue having a predetermined motionresistance. It assumes that the tool surface has sufficient kineticenergy to maintain its velocity constant in spite of the impact. Thefragmenting velocity is affected by: (1) the angle the motion of themoving surface makes with the surface of the tissue; and (2) themomentum of the moving surface.

In the embodiments of FIGS. 1-3, a ring or partial ring having adiameter of two millimeters in the widest distance perpendicular to theaxis of revolution forms a surface of revolution when rotated having atany one time open spaces and a solid cutting ring. The ring is rotatedat approximately 120,000 rpm (revolutions per minute). The solid ring isapproximately 0.50 millimeter wide along the surface of revolution,leaving an open area in the surface of slightly less than nine squaremillimeters and more precisely, 8.9 square millimeters with a length of2.4 millimeters at the longest circle of a segment.

The time between portions of the solid ring sweeping across any surfaceof revolution is approximately every 250 microseconds and should be nolonger than once every three milliseconds (1,000 rpm) but may be asshort as 0.75 of a microsecond (400,000 rpm). With this arrangement andwith parameters adjustable for the particular circumstance, the capsularwall does not enter into the fragmenting zone within and near thesurface of revolution and is not cut and yet the ring is able tofragment the lens for easy aspiration.

In FIG. 4, there is shown a second embodiment of blade portion 14A,having a shaft 18A connected to a blade 17C formed as a partial zone ofa circle or an arc extending from the shaft 18A and having apear-shaped, blade portion 14A with: (1) blunt trailing edges 20; (2)sharpened leading edges 22; (3) a wide base attached to the shaft 18Athat is narrower along the axis of the shaft 18A so that there is at thewide portion, a blunt trailing edge 20 and a sharpened leading edge 22as the cutting blade 17C rotates about the shaft 18A; and (4) an axis ofrotation along the shaft 18A between the base and the narrower upperportion. The apex is generally blunt, but in some embodiments has adrill shape at the apex 24.

It has been found that the sharpened leading edges 22 strain andelongate the cells of higher-mass, rigid material but push away flexibleand low-mass material. The leading edges 22, under some circumstances,cut or scrape fine particles from the harder material that mightotherwise plug the aspirating channel but the cavitation effectfragments the particles into small particles that can easily beaspirated. The blades 17C are shaped to maximize cavitation thatliquifies and stresses lens matter and any viscous fluids and causesfragmentation and mixing of the higher-mass more rigid material. In theembodiment of FIG. 4, the blades have two blunt sides, a top bluntportion 24 and a blunt portion at the mounting base to the tube 18A forstrength at the bottom and to form a non cutting surface at the top.

In FIG. 5, there is shown a top view of the embodiment of FIG. 4, havingthe blade portion 14A with the blade 17C shaped with a thicker portionhaving a blunting surface 24 at its upper end facing away from thedirection of the tubular shaft 18A and rotating thereabout. However, insome embodiments, it has a cutting edge to permit it to provide anabrading center area in the forward direction for positioning at a pointto be fragmented. This embodiment operates substantially the same as theprior embodiments except that its unique shape enables careful placementfor special purposes. Instead of a cutting edge, the top portion 24 maybe bent inwardly or may be blunt to avoid cutting at its top.

In FIG. 6, there is shown a fragmentary, partly diagramatic and partlylongitudinally sectioned view of another embodiment of handpiece 10Awhich is operated by a similar dental drill motor 40 and adapted toreceive a tool by having inserted therein an aspirating drive sleeve 18Bof a tubular sleeve portion 12C substantially identical to that of theembodiments of FIGS. 1-5 except that the blade portion is constructed ina different manner on the end of the inner shaft 18 (FIG. 1-3) as willbe described hereinafter.

The handpiece 10A includes, in addition to the aforementioned motor 40and the aspirating drive sleeve 18B, an outer housing 60 and amotor-tool sleeve coupling 62 with: (1) the motor 40 being connected tothe drive sleeve 18B through the coupling 62 and being located withinthe outer housing 60; (2) the sleeve 18B extending outwardly thereof forrotation by the motor 40 through the coupling 62 during operation of thehandpiece.

To enclose and provide the necessary liquid and vacuum connections tothe operative tool, the outer housing 60 includes a motor housingportion 70 and a tool and coupling housing portion 72 integrally formedtogether with a tubular connector 74 for irrigating fluid, a tubularconnector 76 for aspirating negative pressure and a hole 78 beingprovided through the housing 60 for venting air. The air vent port 78 isan opening extending into and communicating with the interior of themotor housing portion 70 to provide cooling to the motor 40. Theirrigating fluid connector 74 is an opening communicating with theinterior of the housing portion 72 to apply fluid therethrough foreventual passage through a protective sleeve 13A on the outside of thedrive sleeve 18B and to the operating point in a manner to be describedmore fully hereinafter.

The aspirating connector 76 is adapted to receive tubing for applyingnegative pressure through the motor-tool sleeve coupling 62 to theinterior of the drive sleeve 18B to withdraw material during use of thehandpiece 10A. The forward end of the tool and coupling housing portion72 includes external threads 82 which engage internal teeth 112 on theprotective sleeve 13A and a shoulder with an O-ring 80 positioned in itso that the protective sleeve 13A can be threaded onto the outer housing60 to enclose a portion of it sealingly and extend it through its outerend in a manner to be described hereinafter.

To connect the motor 40 to the sleeve portion 12C, the motor-tool sleevecoupling 62 includes a motor output shaft 90, a cylindrical boss 92, acylindrical support member 94, an annular groove 96 within the supportmember 94, two counterbores 98 through the support member 94 at thebottom of the annular groove 96, an opening 100 communicating with theaspirating connector 76 and extending through the cylindrical supportmember 94, a cylindrical opening 95 sized to receive the sleeve 18B anda brazed connection 102 more firmly fastening the support member 94 tothe sleeve 18B. A support 101 receives the motor shaft 90 and the boss92 which rotate within it and are supported by it. The groove 96communicates with the opening 100 as it rotates because of its annularshape and receives vacuum pressure which it transmits through thecounterbores 98 into the sleeve 18B to create negative pressure in theworking tip through this elongated sleeve.

With this arrangement, the sleeve 18B is rotated and carries vacuumpressure with it to the tip. The brazed connection 102 aids intransmitting force from the output shaft 90 to the drive sleeve 18Bthrough the boss 92 by increasing the firmness of the connection betweenthe drive sleeve 18B and the shaft 90.

To mount and support the drive sleeve 18B, the protective sleeve 13A inthe embodiment of FIG. 6 includes a cylindrical base member 110 havinginternal teeth 112 adapted to engage the external teeth 82 of thehousing portion 72 and is sealed against the flow of fluid therethroughby the O-rings 80 compressed between the enlarged cylinder base member110 and the housing portion 72. A narrower outer sheath portion 114 isintegrally formed with the cylindrical base member 110 and receives acylindrical passageway formed between the inner drive sleeve 18B and itsouter tubular surface to permit the flow of irrigating liquid betweenthe outer protective sleeve 13A and the inner drive sleeve 18B into thecapsular bag.

With this arrangement, the drive sleeve 18B can be rotated by the motor40 and at the same time: (1) irrigating fluid can be applied between itand the protective outer sleeve 13A; and (2) aspirating negativepressure can be applied to pull fragments along its longitudinal axis.At its outer end, the fragmenting tip or blades are formed in a mannerto be described hereinafter.

In FIG. 7, there is shown a front, elevational view of one embodiment ofa tool having a sleeve portion 12A and a blade portion 14B with twoblade members formed in its outer end and separated by an opening 123longitudinally passing along the longitudinal axis of the tool to formthe blade portion 14B at the end of the same cylinder forming the sleeveportion 12A. Both the blade portion 14A and the sleeve portion 12A areformed on a single, integrally formed cylinder that serves as anaspirating drive shaft 18B. Aspirating holes extend through the tip ofthe blade portion 14B orthogonal to the longitudinal axis and a slot 120(FIGS. 8 and 9). To receive some material for aspirating, apertures 122and 123 (FIGS. 8-10) are approximately 0.04 inch from the tip 24 (FIG.10) of the blade portion 14B and the diameter of the aspirating driveshaft 18B is approximately 0.042 inch. The diameter of the aspiratingapertures 122 and 123 are 0.018 inch and should not be larger than sevenmillimeters.

In FIGS. 8 and 9, there are shown a plan view and a right elevationalview of the embodiment of FIG. 7, respectively, showing the slot 120having a width of 0.008 inch and extending downwardly approximately 0.07inch. As best shown in FIG. 8, the edges of the walls of the tube orsleeve 18B along the slot 120 have a larger or blunter trailing edgeshown at 126 and a sharper leading edge shown at 124 in one embodimentas well as a blunter edge shown at 130 and a sharper edge shown at 128so that the sharper edges 124 and 128 as the item rotatescounter-clockwise as shown in FIG. 8 looking into the surface of thedrawing elongate or cut the tissue within the eye and create cavitationat the blunter edges 130 and 126.

In FIG. 10, there is shown a fragmentary, front elevational view ofanother embodiment showing the tip 24 along the slot 120A broughttogether, welded and offset to provide a sharper and a blunter edge byoffsetting the edges along the slot 120A to a greater degree but withoutthe need for changing the thickness of the tube walls. This embodimentforms a rake angle of 90 degrees and two cutting edges, but slots atthree locations in the wall of sleeve 18B can also be formed instead oftwo slots 180 degrees apart, providing a 60 degree rake angle and threecutting edges, or four slots can be formed to provide a 45 degree rakeangle and four cutting edges. Moreover, the tips can be brought togetheras in FIG. 10 to form a smooth protective dome or can include a cuttingedge or be open. The tip can also be twisted, which will change the rakeangle along the slot and provide a cyclone fan pulling effect.

To form the embodiments of FIGS. 7-10, a tubular sleeve 18B is slottedat 120 as shown best in FIGS. 11 and 12 and pinched together. The twosides are then offset in space laterally in a direction along a planepassing through the center of the slots and the longitudinal axis of thesleeve as shown in FIGS. 13 and 14 and the tips pinched together andbrazed together to form a tip such as that shown in FIG. 10. Prior toclosing the tips 24, the narrower and blunter edges may be furthershaped by cutting one wall at a more acute angle than the other wall andthen removing the other sides of the slot with a reverse cut to formflat ends and sharpened ends.

To form other raking angles and/or shape the blade to pull viscousfluid, the ends are offset, twisted and brazed as shown in FIG. 15 and16, first offset along a line or plane aligned with the two slots andlongitudinal axis and then twisted at a slightly different angle to forma different rake angle and to create a cyclone pump effect. The tip isnormally smooth at the very tip 24 but has a cutting effect as it movesradially outwardly.

In one version of the preferred embodiment, the tube 18B has an outerdiameter of 42 thousandths (0.042) inch with two diametrically opposedslots. The ends are moved together in a curvature leaving a slot abouteight thousandths inch wide at its widest point and extend from the topapproximately 70 thousandths inch (70 thousandths long). Ninety degreesremoved from the two slots are central aspirating apertures having adiameter of 18 thousandths of an inch and being circular in crosssection. They are located with their bottom edge generally adjacent tothe end of the slots.

The tube usually rotates at approximately 1600 hertz when fragmentingthe nucleus in a preferred embodiment having two cutting edges and thewedged surfaces of the slots have one edge that is in a range of onethousandths of an inch to 20 thousandths of an inch thick and a trailingedge that is in the range of ten thousandths of an inch to 50thousandths of an inch thick. Preferably, it should be in the range of300 hertz to 4000 hertz but may be slower or faster when at a locationin the capsular sac not near tissue to be preserved or which may bemoved to change other tissue. The slots and rate of rotation areselected to provide, in the preferred embodiment, a surface moving 200centimeters a second at the fastest point on the curved moving surfacesand preferably to provide a surface moving at the fastest point within arange of five meters a second to 40 centimeters per second at thefastest point but may move slower or faster under some circumstances.

Since it is a rotating surface which curves inwardly toward the center,the speed is very low at the center and, under some circumstances, doeslittle fragmenting at the center and more and more fragmenting as therotating radius increases to the sleeve radius. The slot is next totissue for a very short time such as between 10 milliseconds and 1millisecond. Each cutting edge sweeps past a point about once every 625microseconds, preferably, or in the normal range of once every 3milliseconds to once every 400 microseconds.

In addition to zones of a sphere and sections of a cylinder intended foruse within an eye, other shapes of moving surfaces may be used and thetool has uses other than for cataract removal, such as in vascularoperations. For example, multiple zones of a sphere may be spaced fromeach other at a shorter distance so that the item need not be rotated asfast and motion other than rotational motion may be used to prevententrance of the tissue into the fragmenting zone. A convenientembodiment for removing structures around veins or arteries duringvascular operations is dumbbell shaped so that a recess fits around thevein while spherical cutting zones are positioned on either side of thevein.

In some embodiments, the moving surface is formed of a curved memberattached to a rotatable shaft having a sharpened edge at an angle ofbetween 0 and 60 degrees but preferably 45 degrees with a surface ofrevolution, which surface has a center of rotation aligned with therotating shaft. The sharpened edge of the curved member may face awayfrom the center of rotation so that the cutting action of the sharpenedsurface is into the cortex and core material of a cataract.

In FIG. 17, there is shown a block diagram generally illustrating thesteps in a cataract extraction and lens implantation technique 50comprising: (1) the step 52 which includes the preliminary substeps ofmaintaining the anterior chamber and making the incision into thecapsular wall; (2) the step 54 of removing the lens by fragmenting itand aspirating it with the rotating member; and (3) the step 56 whichincludes the substeps necessary for implanting the lens.

In performing this technique, the step 52 which includes the substepsrequired to make the incision and maintain the anterior chamber and thestep 56, which includes the substeps necessary for implanting the lensare not by themselves new and many of the steps are described in Anis,Aziz Y., "Illustrated Step-by-Step Description of the Anis Dry ExtraCapsular Cataract Extraction Technique With In-the-Bag LensImplementation", Seminars in Opthalmology, v. 1, N. 2 (June), 1986, pp.113-129. Moreover, the removal of the lens may not be followed byimplantation but may be part of a treatment in which the aphakia istreated by contact lens or glasses.

The step 54 of removing the lens by fragmenting and aspirating it withthe rotating member includes: (1) the step of inserting the handpiece;(2) the step of breaking and removing the hardened part of the nucleus;and (3) the step of aspirating particles of tissue. These steps are allperformed through a small incision while the anterior chamber ismaintained with a viscoelastic medium. Hydrodelineation may be performedas described in U.S. Pat. No. 4,908,015, if desired, but suchhydrodelineation is not part of this invention. If necessary, vitreousfluids may be aspirated.

The step 52 which includes preliminary substeps of maintaining theanterior chamber and making the incision in the capsular wall includesthe substep of making a small incision in the capsular bag, preferablyno greater than three millimeters in length and in the range of one totwo millimeters. This incision is made while the anterior chamber ismaintained and is made as small as possible to maintain the structure ofthe capsular bag to the extent possible. Through this small incision,the step 54 of fragmenting and aspirating and the step 56 of implantinga lens are performed. Under some circumstances, the incision may be fouror five millimeters but should always be less than 7 millimeters.

With the posterior capsule in focus in the focal plane of themicroscope, the handpiece 10 is introduced through an incision shown at220 in FIG. 18 in the wall of the capsular sac. The tip of a handpiece10 is thrust through the incision in the wall of the capsular bag andinto the lens therein.

The tip is rapidly rotated and linearly vibrated in a direction normalto the plane of rotation while slight negative pressure is applied toaspirate the fragments. The rotating tip is inserted gradually into thecortex and nucleus and, from time to time, a small amount of irrigatingfluid is injected. Fragmented cortex or nucleus material is aspirated.The speed of rotation and vibration can cause the particles to be sofine as to be substantially invisible and not to interfere withvisibility of the surgery. The rotation and aspiration mix the smallparticles and easily pull them into the instrument. The same handpiececan be used to remove vitreous fluids. After removal of the cataract andthe handpiece with the capsular sac relatively intact, a lens implant isinserted through a relatively small opening as described in the abovepublication of Anis.

Generally, the nucleus is first removed then the cortex. Thesurface-discriminating, fragmenting handpiece fragments and permitsaspiration of the cotex and nucleus without damaging nearby smooth wallsof the capsular sac. It avoids fragmenting the smooth walls with itscutting edges but fragments rougher, stiffer higher-mass tissue, movingit into a negative pressure zone for aspiration. The smooth moreflexible, lower mass surfaces are moved by the blades which hit it at anangle. The tissue being fragmented is hit at an angle and is subject tocavitation rapidly and repeatedly with a force each time that does notmove the entire material to the extent that it may damage the capsularwall or other healthy tissue that is not to be fragmented but doesfragment the cortex.

The surface discrimination of the instrument is controlled by movingsurfaces which permit the diseased higher-mass tissue to be fragmentedbut which move at a rate of speed and have openings between them of sucha size that the more integrated flexible, lower-mass and smoother tissuedoes not fall within their fragmenting zone. The tissue is notconstrained by opposed shear forces of the instrument but are free tomove and the cutting edge of the instrument cuts tissue that: (1) isstiffer and has a higher modulus of rigidity; and (2) is at an angle tothe cutting edge closer to 90 degrees and receives less force moving itaway.

Thus, the surgeon removing a cataract adjusts the speed of movement ofthe cutting edge to cut cortex with a higher-mass and modulus and moreprojections in the path of the cutting surface and not the capsular wallwith a lower modulus and mass and fewer projections closer to 90 degreesso it is more readily moved away from the cutting edge. The aspiratingpressure is low enough to pull the fragmented tissue but not the smoothwall. The rotating surfaces move the smooth wall outwardly and providesome counter pressure to the aspirating pressure inside the cuttingzone.

In u sing this instrument, as the lens is reduced in mass and freed fromits connection to the structure of the eye by fragmentation, itstendency to move away from the cutting edges is increased one way ofcompensating for this effect may be by changing the speed, the locationand the direction in which the cutting edges impact the lenssufficiently often to neutralize the tendency of the impact to move thelens in one direction. Another aid is to rotate the tip to mix theparticles with fluid and pull the fluid and particles into theinstrument. This is done by continuously rotating the tip in onedirection while ultrasonically vibrating it. Continuous rotation in onedirection means rotation in one direction for more than one 360 degreecycle of rotation. Without such rapid impact, the impacting may causethe lens to move, such as by causing rotation of the lens.

In FIG. 19, there is shown a fragmentary, partly diagramatic and partlylongitudinally sectioned view of still another embodiment of handpiece10B especially useful after the lens has been reduced in size. Insteadof being operated by a dental drill motor 40, it is driven by a vibrator40A, which may be any conventional type of vibrator such as those usedto operate the tip in the above-mentioned U.S. Pat. Nos. 3,589,363 toAnton Banko, et al., 3,902,495 to Steven N. Weiss, 3,693,613 to CharlesKelman, et al, and 4,041,947 to Steven N. Weiss, et al. Except for thedrive mechanism, the handpiece 10B is identical to the embodiment ofFIG. 6 and the reference numbers for identical parts remain the same.

The handpiece 10B includes, in addition to the aforementioned vibrator40A, an aspirating drive sleeve 18B, an outer housing 60 and amotor-tool sleeve coupling 62 with: (1) the vibrator 40A being connectedto the drive sleeve 18B through the coupling 62 and being located withinthe outer housing 60; (2) the sleeve 18B extending outwardly thereof forvibrating curvalinear motion by the vibrator 40A through the coupling 62during operation of the handpiece 10B.

The vibrator 40A includes a conventional oscillator 130, a source of dcpower 132, and a piezoelectric or electromagnetic vibrator 134electrically connected in series with the switch 20 (FIG. 1) to beenergized and vibrate the cutting edges (not shown in FIG. 19) connectedto the sleeve portion 12C as explained in connection with the embodimentof FIG. 6. A shaft 90A is mounted for rotation in bearings 138 andincludes a welded arm extending orthogonally and radially therefrom,biased into contact with or fastened to a movable portion of thevibrator 134 so that vibration of the vibrator imparts rotating motionto the shaft 90A.

To connect the vibrator 40A to the sleeve portion 12C, the motor-toolsleeve coupling 62 includes the vibrator output shaft 90A, a cylindricalboss 92, a cylindrical support member 94, an annular groove 96 withinthe support member 94, two counterbores 98 through the support member 94at the bottom of the annular groove 96, an opening 100 communicatingwith the aspirating connector 76 and extending through the cylindricalsupport 94, a cylindrical opening 95 sized to receive the sleeve 18B anda brazed connection 102 more firmly fastening the support member 94 tothe sleeve 18B.

The bearing support 101 receives the vibrator shaft 90A and the boss 92which rotationally vibrate within it and are supported by it. The groove96 communicates with the opening 100 as it moves because of its annularshape and receives vacuum pressure which it transmits through thecounterbores 98 into the sleeve 18B to create negative pressure in theworking tip through this elongated sleeve.

With this arrangement, closing the switch 20 (FIG. 1) connects powerfrom the power supply 132 to the oscillator 130. The vibrator 134 thenvibrates at the frequency to which the oscillator 130 has been tuned bythe surgeon, which vibrator 134 being energized through conductors 139.The vibrator 134 reciprocates a lever 136 turning the shaft 18Brepeatedly. This causes the lens to be impacted with the cutting edgesat an angle and speed that avoids damage to the capsular wall, if itshould be near, and fragments the lens.

In FIG. 20, there is shown a partly longitudinally sectioned,fragmentary, simplified view of a handpiece 10C, having as its principalparts an ultrasonic vibrator 40C, an electrical rotational motor 40D anda aspirating tube 18C all in line with each other along a commonlongitudinal axis. The motor 40D is coupled to the ultrasonic vibrator40C, which in turn is coupled to the aspirating tube 18C to impart acombined rotary and longitudinal ultrasonic reciprocating motion to theaspirating tube 18C.

With this mechanism, the aspirating tube 18C moves the fragmenting tip14C (not shown in FIG. 20) so that it rotates rapidly, and whilerotating, ultrasonically vibrates in and out of the tissue once for eachsmall, angular increment of rotational motion, such as for example,every one degree or less. Thus, it combines the rotational movement andultrasonic movement of prior embodiments. While the motor 40D isintended to continuously rotate the aspirating tube 18C in a singledirection, such as clockwise or counterclockwise, it can alternaterotations, between clockwise and counterclockwise in the manner of theembodiment of FIG. 19. In this manner, the time of impact is primarilydetermined by the frequency of the ultrasonic, reciprocal motion and thelocation and direction are primarily controlled for a stationaryhandpiece by the rotational speed. By selecting the optimum or nearoptimum values of rotational speed and reciprocating frequency, movementof the mass of tissue with respect to fragmenting speed may becontrolled.

The embodiment 10C of FIG. 20 is similar to prior embodiments in that itincludes a tubular aspirating connector 76 and an irrigating connector74 to aspirate through the center of the aspirating tube 18C andirrigate between the protective sleeve 12D and the aspirating tube 18Cin the manner described in previous embodiments. In the embodiment ofFIG. 20, the outer housing 60C encloses both an ultrasonic vibrator 134(FIG. 19) adapted for reciprocally vibrating the aspirating tube 18C towhich the fragmenting tip is connected in a direction aligned with thelongitudinal axis of the handpiece 10B and the tip and the rotationalmotor 40D coupled through a coupled mechanism 150. The necessaryelectrical connections are supplied through an opening in a rearbulkhead 152.

In FIG. 21, there is shown a fragmentary, sectional view of anotherembodiment of fragmenting tip 14C having tubular, cylindrical walls 164enclosing an aspirating section 162, which communicates with theinterior of the aspirating tube 18C (FIG. 20). The end of the tip 14C isrounded at 158 and in one embodiment, may be roughened. An opening 156,communicates with the aspirating section 162 and provides a slight,inward pull of tissue.

To fragment tissue, the opening 156 is blunt and able to grip tissue androtate it as tissue is pulled inwardly. Reciprocating ultrasonicvibration of the tip causes cavitation and rotation causes twisting. Therotation may also cause small particles to be formed and a central plugto be twisted free and mixed with liquid and aspirated.

In operation, the tube 18C is rotated while ultrasonic vibrations areapplied along its rotational axis so that it reciprocates in and out oftissue a large number of times for each rotation. For example, therotation may be between 100 and 15,000 revolutions per minute andpreferably between 4,000 and 5,000 revolutions per minute while theultrasound vibtrations may be applied within a range of 10 kilohertz to500 kilohertz and preferably 40 kilohertz. The exact frequency ofreciprocating vibration and rotational speed may be selected by thesurgeon and may even extend to lower speeds and frequencies or higherspeeds and frequencies depending on the nature of the cataract beingfragmented. The tip of the tube should be symmetrical rather than chiselshaped so as to be visible when rotating and reciprocating and may havea continuous distal edge but must be shaped to remove tissue bycavitation.

The frequency of vibration and the speed of rotation are selected sothat the tip moves inwardly into the tissue at every small fraction ofrotation, such as at every degree of rotation to not impart excessivemotion to the mass of the tissue but to cause removal of the tissue as afine powder.

The combined integrated technology of this surgical tool provides addedconvenience and functions normally in separate available surgicalhandpieces. Size reduction due to advancing technology, in conjunctionwith the physician's desire for smaller surgical wound sites andprecision tissue removal, allow this handpiece to incorporate bothrotary action and ultrasonic fragmentation. It permits vitrectomy andremoval of fragmented cateract with the same handpiece tip. Whenoperating at 40 kHz (which is the most commonly effective frequency forultrasonic systems), this handpiece delivers 0.012 inch of strokedisplacement. The constant stroke feature provides consistent powerthrough any hardness of tissue.

The rotary action assists the ultrasonic fragmentation of the tissue, bytumbling the fractured particles at the distal end of the ultrasonictip. This allows the tip to acquire a new surface of tissue without theneed for a second manipulation instrument. This allows smaller "bites"and reduces propensity for "coring" or "plunging" and subsequentparticles are aspirated through the ultrasonic tip. The inner plug oftissue is twisted free of larger bodies and aspirated.

The added fluid action from the rotation enhances a "capture zone"forming a larger funnel shaped suction pattern that enhances flow to thetip. Just outside this region is a turbulent zone that rejects(protects) tissue. The speed of rotation increases or decreases thisaction. Working in conjunction with the aspiration and infusion, therotation enhances the ultrasonic action.

In FIG. 22, there is shown a block diagram of an interface 170 between aphacotmesis handpiece 10C and any one of a plurality of incompatibleconsoles 21A which consoles may be electrically incompatible with thephacotmesis handpiece 10C. The consoles 21A may be of the type used fora hydrosonic type of ocular operation or phacoemulsification type ofocular operation.

For this purpose, the interface 170 includes a handpiece simulator 174,a power supply 176, an ultrasonic driver 178, and a motor driver 180.The power supply 176 and the motor driver 180 are conventional. Thepower supply 176 is adapted to be connected through conductors 172 toconventional power mains. It supplies DC power to the handpiecesimulator 174, the ultrasonic driver 178 and the motor driver 180through the conductor 182.

The handpiece simulator 174 is electrically directly connected to theconsole 21A and matches the output impedance of the console to theimpute impedance of the handpiece to obtain efficient power transfer ofthe control signal from the console to the drivers. The fluidicconnections are connected directly from the console 21A to thephacotmesis handpiece 10C since they are generally compatible. Theconsole 21A and the handpiece simulator 174 together provide theappropriate signal to determine at least the amplitude of ultrasonicvibration by the ultrasonic driver 178. The frequency of the ultrasonicvibrations and the rate of rotation by the motor driver 180 may be seton the handpiece 10C or by the synergist and may or may not be varied bysignals from the console 21A depending on the design of the instrumentand console.

To enable the connection of a plurality of different consoles to aphacotmesis handpiece 10C, the handpiece simulator 174 includes a rotaryswitch that is adapted to interconnect any other of a plurality ofdifferent impedances to the input connectors leading to the console 21A,with the input impedances being selected to match the output impedancesof the different consoles. Instead of utilizing control signals from theconsole 21A, the interface 170 may include individual, manually,adjustable attenuation devices or amplifiers to control the ultrasonicdriver 178 and the motor driver 180 individually to set rates ofultrasonic vibration of the tip and corresponding rates of rotation ofthe tip or a combination of the two from a single switch.

In FIG. 23, there is shown a schematic circuit diagram of the handpiecesimulator 174 having an input transformer 190, lumped parameterimpedances 192, a selector switch 194, and output terminals 196. Thetransformer 190 is adapted to have its primary electrically connected toa console 21A (FIG. 22) and the output terminals 196 are adapted to beelectrically connected to the ultrasonic driver 178 (FIG. 22) and to themotor driver 180 (FIG. 22). The lumped parameter impedances 192 and theselector switch 194 are adapted to be electrically connected in circuitwith each other and between the transformer 190 and the output terminals196. The switch 194 may be open to disconnect the console, closed to afirst terminal to connect one value of impedance or to a second terminalto electrically connect in circuit a second impedance so that thehandpiece simulator 174 may provide an input impedance which matches theoutput impedance of a console to which the handpiece is intended to beconnected.

In FIG. 24, there is shown a block diagram of an ultrasonic driver 178having input terminals 200, a high voltage power supply 202, a variablepower supply 204, a tuning module 208, a power amplifier 206, animpedance matching network 210 and output terminals 212. The inputterminals 200 are electrically connected to the handpiece simulator 174(FIG. 22) to receive control signals. These control signals are appliedto drive the DC motor driver 180 (FIG. 22) and are applied to the poweramplifier 206 and the variable supply 204. The variable power supply 204receives power from the high voltage supply 202 and supplies a selectedvoltage to the power amplifier 206 under the control of the controlsignal through input terminals 200. This signal determines the amplitudeof the signal applied to the impedance matching network 210. Thefrequency of that signal is adjusted by the tuning module 208 under thecontrol of a computer or the direct control of a surgeon. The outputfrom the matching network 210 drives the ultrasonic vibrator and thehandpiece 10C (FIG. 22).

In use, the interface is connected to a console and to the phacotmesishandpiece and the rotary switch is switched to the appropriately labeledconsole to provide efficient power transfer by impedance matching. Inthe preferred embodiment, the control signal from the console is used tocontrol both the rotational speed and the vibration speed.

After preparation for phacotmesis, the lens is preferably grooved toform three delineated sections. This may be done by a first groove madein the lens of the eye which is then bifurcated by two grooves, usingthe phacotmesis instrument described above with the ultrasonicallyvibrating and rotating tip extending slightly, such as zero to twomillimeters beyond the distal end of the irrigating sleeve. After thefirst groove is made, the nucleus is fractured such as by crackingforceps, then the second groove is made in the larger fragment and thatfragment is fractured.

The phacotmesis tip is then retracted slightly until it is level withthe irrigation sleeve. It may extend slightly for very hard lensmaterial and may be retracted slightly for soft lens material but isapproximately level. The tip is then positioned on a surface of one ofthe fragments and held by oclusion. The phacotmesis tip is activated andthe resulting fragments are one-by-one aspirated. More specifically, theinstrument includes a blunt zero degree tip configuration with a centralopening of 0.6 mm caliber and a sophisticated micro motor that providesthe tip with rotary capability simultaneously with its ultrasonicactivity at speeds reaching up to 5,000 or 6,000 rpms and 40 Khzvibration. The optimum rotational speed has been found to be 4,000 rpm.The combination of the two movements (the linear ultrasound and highspeed rotary), give the blunt tip a sufficient cutting capability to cuta groove in the nucleus with apparently no resistance at all asdemonstrated by the lack of any movement and the complete stability ofthe nucleus during the cutting. One can therefore create short, verydeep grooves at an obtuse or nearly obtuse angle of the tip to thenuclear surface without fear of clogging or lollipopping the nucleus. Bycontrast, with the standard Phaco tip one needs a longer runway and manymore passes since it is imperative to avoid complete occlusion duringsculpting.

And incision is made with a 2.65 mm diamond Keratone even though a 2.50mm incision is quite enough. The sharp side of the Keratome is pressed(without any slicing motion), over the temporal limbus just outside theclear cornea to create the external incision line and the Keratomeintroduced through this line to enter the anterior chamber, forming a2×2.6 corneal valve. A paracentesis incision is made with a diamondlance at six o'clock in the left eye or twelve o'clock in the right eye.

A 0.12 mL volume of Xylocaine 1% without preservation is injected intothe anterior chamber and the chamber is filled with Viscoelastic. A 25gauge needle is used, (straight, without bending the tip), to puncturethe anterior capsule at the center and moved sideways cutting thecapsule with its sharp bevel until the position of the desiredcircumference of the capsulorhexis. The tip of the needle is now used topick the cut edge of the capsular membrane forwards to create a dog-ear.A microforceps is now used to complete the Capsularhexis.

Careful attention to this step is of paramount importance, and whenperformed properly, can save the surgeon the step of aspirating thecortex. A canula is used to perform manual hydrodissection. This canulais a 29 gauge canula with the port to the side of the very tip, which isblunt and rounded. Keeping the port posterior, the configuration of thetip permits it to be threaded underneath the cut edge of thecapsularhexis, gently lifting the anterior capsule from the cortexwithout picking any of the cortical fibrils. The canula is then advancedperipherally very gently until resistance is felt and the cut edge ofthe capsulorhexis moves with very gently nudges of the canula. Thisinsures that the tip of the canula is now at the capsular equator withthe port facing backwards. Injection of BSS at this point almostinvariably cleaves the whole capsular membrane from the cortex.

To make a dividing groove in the lens the following parameters are used:(1) simultaneous ultrasound rotation; (2) ultrasound ceiling: 40%; (3)rotational speed: 3,000 rpm; (4) vacuum: 10 mm Hg; (5) aspiration flowrate: 20 mL/min; (6) infusion bottle: height 85 cm; (7) continuous flow;and (8) surgeon control.

The tip is now introduced in the anterior chamber with the irrigationsleeve retracted just enough for the desired groove depth. A deep shortgroove along the diameter of the nucleus is now made with 2-4 onedirectional deep passes. This is significantly different from themultiple to and fro shallow passes with standard Phaco.

A cracking forceps is used to divide the nucleus into two halves alongthe groove. Then with the cracking forceps still inside the anteriorchamber, it is used as a manipulating instrument to rotate the nucleusso that the fracture line lies 90 degrees to the axis of the tmesisinstrument, one half of the nucleus now is nasal and the other half istemporal.

To aspirate the nuclear halves, the following parameters are used: (1)simultaneous ultrasound and rotation; (2) ultrasound ceiling: 40%; (3)rotation speed: 3,000 rpm; (4) vacuum: 120 to 150 mm HG; (5) aspirationflow rate: 25-30 mL/min; (6) infusion bottle height: 85 cm; (7)continuous flow; and (8) surgeon control.

With these parameters the tip is now introduced into the anteriorchamber and the central bulk of the nasal fragment is removed usingshort radial strokes, or better still, a side to side wiping motion ofthe tip. The nasal nuclear half now looks more less like a quarteredorange peel. The silent tip is now used to gentle nudge it towards theequator and forwards. This maneuver almost invariably tumbles thenuclear half backside forwards, delivering its equatorial margin intothe center of the pupil. The fragment is now attached at its equator.The most productive way of using tmesis to aspirate the nuclear fragmentis to apply the silent tip to it's surface so that the axis of the tipis 9 degrees to the plane of the surface in order to occlude the zerodegree tip and engage with aspiration.

The fragment is held in mid-pupil just posterior to the iris plane andthe foot control is used to initiate rotary and reciprocation power. Abig chunk of the nucleus will be gulped. By repeating this step once ortwice the remains of the nasal nucleus and cortical half is eliminated.Aspiration requires initial occlusion of the tip prior to applyingultrasound and rotation so that the fragment does not chatter. However,because tmesis does not permit coring and filling up or blocking of thelumens of the tip, negative pressure inside the tip, or time to buildup, there is no surge and the anterior chamber remains remarkablystable.

During the aspiration of the nasal nuclear half the tmesis tip issupported over the temporal half, which protects the posterior capsulefrom coming forwards at any time. Now the temporal half is rotated tooccupy the nasal half of the capsular bag and a nuclear manipulator isintroduced through the paracentesis incision and held steadily posteriorto the tmesis tip to keep the posterior capsule from coming forwardsduring the aspiration of the remaining nuclear fragment. This is theonly function that uses the second instrument.

The tip is now applied to the center of the anterior edge of thefractured surface of the nuclear half. Aspiration is applied to engageit and the tmesis tip eats into the remaining nuclear half. The secondnuclear half almost always rotates spontaneously tumbling itself todeliver its equatorial margin within the pupil area. At the same time itbecomes constricted in the center so that it assumes an hour glass likeshape. The steps of occlusion and then tmesis are applied until it iscompletely eliminated. As mentioned before, if hydrodissection wasefficiently performed there is no cortex remaining. If there is anyresidual cortex remaining with the tmesis tip sill inside the anteriorchamber, the mode is changed to aspiration/irrigationonly and the cortexis aspirated.

The incision is now enlarged to the desired size with proper sizedKeratome. The viscoelastic of choice is injected to inflate the capsularbag and the foldable 10L of choice is implanted into the capsular bag.The tip in aspiration/irrigation mode is used to aspirate theViscoelastic from the anterior chamber.

As can be understood from the above description, the technique andequipment of this invention has several advantages, such as: (1) theyselectively fragment some tissue without damaging other nearby tissue;and (2) they are able to fragment, mix and aspirate tissue, and in thecase of cataract removal, also scrub the capsular wall without damagingit, all with one instrument.

Although a preferred embodiment of the invention has been described withsome particularity, many modifications and variations are possible inthe preferred embodiment without deviating from the invention.Therefore, it is to be understood that within the scope of the appendedclaims, the invention may be practiced other than as specificallydescribed.

What is claimed is:
 1. A method comprising the steps of:inserting a fragmenting tip having fragmenting surfaces through an opening in an eye into a lens of the eye having a cataract and a capsular wall wherein the tip has at least one movable fragmenting surface; moving the fragmenting surface in a first direction and in at least a second direction; the step of moving the fragmenting surface in a first direction including the step of rotating the fragmenting surface at a first value of cycles per second sufficient to twist fibrous material until said fibrous material fails; and the step of moving the fragmenting surface in a second direction including the step of reciprocating the fragmenting surface at a second value of cycles per second sufficient to cause cavitation of hydrated material; said second value being different than the first value and being in the ultrasonic frequency range.
 2. A method according to claim 1 further including the steps of:positioning the fragmenting tip to impact the tissue of the cataract while said fragmenting tip is moving at a velocity higher than the fragmenting velocity with respect to the capsular wall and at an angle to the cataract; whereby the cataract is fragmented but not the capsular wall; and aspirating the fragmented tissue.
 3. A method according to claim 2 in which the step of inserting the fragmenting tip includes the substeps of:making a small incision less than 7 millimeters in diameter in a capsular sac along the margin; and inserting the fragmenting tip into the capsular sac.
 4. A method according to claim 1 in which:the step of rotating the fragmenting surface includes the step of rotating the fragmenting surface about a longitudinal axis of the, fragmenting tip; and the step of inserting the tip includes the step of inserting the tip with the longitudinal axis making an acute angle with the capsular wall wherein the rotating fragmenting surfaces impact the tissue of the cataract at an angle.
 5. A method according to claim 1 in which the fragmenting tip is rotated with a power level of less than 1 horsepower.
 6. An apparatus for removing tissue from a patient comprising:means for fragmenting and aspirating tissue having an operative tip; said means for fragmenting and aspirating tissue comprising means for repeatedly and cyclically moving the operative tip under the control of an electrical signal at a low power level in a first direction and in at least a second direction, wherein the number of cycles per unit time in the first direction is different than in the second direction; said operative tip having at least one fragmenting surface; the means for moving the fragmenting surface in a first direction including means for rotating the fragmenting surface at a speed sufficient to twist fibrous tissue to failure and; the means for moving the fragmenting surface in a second direction including means for reciprocating the fragmenting surface at an ultrasonic frequency sufficiently to cause cavitation.
 7. Apparatus in accordance with claim 6 in which the operative tip includes at least one fragmenting surface and at least of the fragmenting surface include at least one cavitation-creating surface.
 8. Apparatus according to claim 6 in which the operative tip includes at least two fragmenting edges and the space between fragmenting edges is less than 5 millimeters.
 9. Apparatus according to claim 6 in which the operative tip is tubular and has a diameter of less than 7 millimeters.
 10. Apparatus according to claim 6 in which the operative tip is hollow and includes slots extending generally in a plane parallel to the longitudinal axis of the operative tip, said slots having a leading edge and a t railing edge.
 11. Apparatus according to claim 6 in which the operative tip is replaceable. 